Portion of a periphery



FIG. 1 is a perspective view of the portion of a periphery showing my new design;

FIG. 2 is a bottom plan view thereof;

FIG. 3 is a right side elevational view thereof;

FIG. 4 is a front elevational view thereof; and,

FIG. 5 is a rear elevational view thereof.

The broken lines shown throughout the views illustrate the environment in which the design resides, and form no part of the claim. 

The ornamental design for a portion of a periphery, as shown and described. 